The present invention refers to a throttle-butterfly connector piece for an internal combustion engine which connector piece has a throttle butterfly which can be turned by a setting shaft which is passed through a setting-shaft passage into the throttle-butterfly connector piece. Such throttle-butterfly connector pieces are provided in the internal combustion engines of modern automotive vehicles and are generally known.
In modern automotive vehicles the idling speed of rotation is not simply set to a given value for an average load but is adjusted by means an electronic regulator to a desired value which lies under all conditions of load only slightly above the stalling point of the engine. In this way the consumption of fuel and the contaminating of the environment by injurious exhaust gas are reduced.
In throttle-butterfly connector pieces with throttle butterfly it is disadvantageous for such idling speed adjustments that the free air-passage cross section of the throttle-butterfly connector piece increases very rapidly at the start of the opening of the throttle butterfly even with only small angles of opening of the throttle butterfly. Since the throttle butterfly is not suitable for this reason as setting member for the adjustment of the idling speed, modern idling speed controls contain a bypass which bypasses the throttle butterfly and within which an idling speed setter is arranged as setting member. This naturally results in a considerable expense, with the result frequently that the entire idling speed control is considered too expensive.